The olefin polymerization catalyst is the core of polymerization technology of polyolefin. As seen from the progress of olefin polymerization catalyst, there are mainly two aspects: (1) development of a catalyst capable of producing polyolefin resin with a special performance or better performance, such as metallocene catalyst and non-metallocene late transition metal catalyst; (2) simplification of the catalyst production process, reduction of catalyst cost, and development of environment-friendly technology to improve benefit and enhance competitiveness, based on a further improvement of the performance of the catalyst, for the production of general polyolefin resin. Before the 1980s, the research of polyethylene catalyst was focused on the pursuit of catalyst efficiency. After nearly 30 years of efforts, the catalytic efficiency of the polyethylene catalyst has been improved, the polyolefin production process is simplified, and the energy consumption and material consumption are reduced.
Patents CN201010186264.2 and CN200910092169.3 disclose a supported catalyst consisting essentially of a carrier, a titanium halide and an electron donor, wherein the titanium halide is added directly into the catalyst components.
The present application has found that the polymerization or copolymerization of ethylene can be efficiently catalyzed by a catalyst system composed of a main catalyst, produced by loading titanium halide generated by in-situ reaction between titanate and silicon halide onto a carrier during the preparation of the catalyst, and a co-catalyst. The main catalyst prepared by the present invention has particles with good morphology, a high loading capacity, and a high activity, and the catalyst will not peel off from the carrier, and is applicable to a slurry method, a vapor phase polymerization process, or a combined polymerization process.